Stereoscopic technology is used to create realistic games or scenery providing depth to objects, by presenting a unique view to each eye of a viewer almost the same way the viewer would view objects in real life. In polarization technology, linear polarized and circularly polarized lights as well as a combination thereof, referred to as elliptically polarized light, are used.
A conventional stereoscopic display system uses passive polarized stereoscopic glasses comprising two filters at 90° from each other and generates two images polarized at 90° from each other. FIG. 1 illustrates such a system, where L.I. is a left image intended to be seem by the left eye only, R.I. is a right image intended to be seem by the left eye only, L.F. is a polarized left filter, which lets only the left image go through, and R.F. is a polarized right filter, which lets only the right image go through.
In liquid crystal display (LCD) technology, three types of active matrix Thin Film Transistor (TFT) LCD are used: Twist Nematic (TN), In-Plane Switching—(IPS) and Multi-domain Vertical Alignment (MVA). A LCD display consists essentially of two sheets of glass separated by a sealed-in liquid crystal material, which is normally transparent. A voltage applied between front and back electrode coatings disrupts an orderly arrangement of the liquid crystal molecules, darkening the liquid enough to form visible characters.
In a U.S. Pat. No. 5,629,798 issued to the present applicant, a deep 3D perception is achieved by showing two images from a different point of view corresponding to each eye of the viewer, as in stereoscopy, with a unique advantage of displaying the two images without multiplexing them in time nor in space as is usually the case in most others stereoscopic technologies. The method consists in adjusting, for each picture element individually, the intensity of light as a function of the intensity value of two corresponding pixels in the left and right images, and polarizing, for each picture element individually, at an angle depending on the value of the two corresponding pixels of the left and right images. The resulting display is similar to any conventional LCD monitor but it comprises two LCD panels. The display comprises a series of layers, comprising, from back to front, a back light panel, a first polarized filter, a first LCD panel (Mod LCD), a second polarized filter and a second LCD panel (Ang LCD). The first LCD panel controls the pixel intensity for both eyes while the second LCD panel controls the distribution to one eye or the other. To generate a stereoscopic image, the left and right images are converted into a modulo (driving the first LCD) and an angular (driving the second LCD) images using the following relations:
                    Modulo        =                              (                                          left                2                            +                              right                2                                      )                                              (        1        )                                Angular        =                  arctan          ⁡                      (                          left              right                        )                                              (        2        )            
The orthogonal polarized filters of the passive glasses recreate the left and the right image for the left and the right eyes, since these polarized filters act as cosine and sine trigonometric functions as follows:
                                                        (                                                left                  2                                +                                  right                  2                                            )                                ·                      Cos            ⁡                          (                              arctan                ⁡                                  (                                      left                    right                                    )                                            )                                      =        left                            (        3        )                                                                    (                                                left                  2                                +                                  right                  2                                            )                                ·                      Sin            ⁡                          (                              arctan                ⁡                                  (                                      left                    right                                    )                                            )                                      =        right                            (        4        )            
In spite of developments in the field, there is room for further improvements in the field of high quality flat panel stereoscopic displays.